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101.
刘莎  龚财惠  符州 《重庆医学》2015,(8):1085-1086,1090
目的:探讨呼出气一氧化氮检测用于评估临床缓解期哮喘儿童病情的价值。方法选取214例处于临床缓解期哮喘儿童,按照有无进行规范化治疗分为治疗组和对照组。同时记录FeNO及PC20 FEV1数值。结果治疗组与对照组平均FeNO值分别为22.63×10-9 ppb和39.67×10-9 ppb ,差异有统计学意义( P<0.01)。治疗组与对照组平均 PC20 FEV1数值分别为(7.43±6.16)和(6.78±5.83),差异无统计学意义(P>0.05)。FeNO与PC20 FEV1呈负相关性(r=-0.372,P<0.01),直线回归方程为Y=35.883-1.074X(X表示PC20 FEV1,Y 表示FeNO)。结论 FeNO数值可以作为哮喘患儿非特异性气道炎症控制状况的可靠指标。呼出气一氧化氮检测与支气管激发试验联合,可显著提高临床缓解期哮喘患儿的诊断率。  相似文献   
102.

Background and Purpose

β‐Arrestins function as signal transducers linking GPCRs to ERK1/2 signalling either by scaffolding members of ERK1/2s cascades or by transactivating receptor tyrosine kinases through Src‐mediated release of transactivating factor. Recruitment of β‐arrestins to the activated GPCRs is required for ERK1/2 activation. Our previous studies showed that δ receptors activate ERK1/2 through a β‐arrestin‐dependent mechanism without inducing β‐arrestin binding to the δ receptors. However, the precise mechanisms involved remain to be established.

Experimental Approach

ERK1/2 activation by δ receptor ligands was assessed using HEK293 cells in vitro and male Sprague Dawley rats in vivo. Immunoprecipitation, immunoblotting, siRNA transfection, intracerebroventricular injection and immunohistochemistry were used to elucidate the underlying mechanism.

Key Results

We identified a new signalling pathway in which recruitment of β‐arrestin2 to the EGFR rather than δ receptor was required for its role in δ receptor‐mediated ERK1/2 activation in response to H‐Tyr–Tic–Phe–Phe–OH (TIPP) or morphine stimulation. Stimulation of the δ receptor with ligands leads to the phosphorylation of PKCδ, which acts upstream of EGFR transactivation and is needed for the release of the EGFR‐activating factor, whereas β‐arrestin2 was found to act downstream of the EGFR transactivation. Moreover, we demonstrated that coupling of the PKCδ/EGFR/β‐arrestin2 transactivation pathway to δ receptor‐mediated ERK1/2 activation was ligand‐specific and the Ser363 of δ receptors was crucial for ligand‐specific implementation of this ERK1/2 activation pathway.

Conclusions and Implications

The δ receptor‐mediated activation of ERK1/2 is via ligand‐specific transactivation of EGFR. This study adds new insights into the mechanism by which δ receptors activate ERK1/2.

Abbreviations

DPDPE
[D‐Pen2, D‐Pen5] enkephalin
HB‐EGF
heparin‐binding EGF‐like growth factor
IGFR
insulin‐like growth factor receptor
NG108‐15
cell mouse neuroblastoma x rat glioma hybrid cell
RTK
receptor tyrosine kinase
TIPP
H‐Tyr‐Tic‐Phe‐Phe‐OH
  相似文献   
103.
Titanium dioxide (TiO2) nanomaterials (NMs) have found widespread applications owing to their attractive physical and chemical properties. As a result, the potential adverse impacts of nano‐TiO2 exposure on humans have become a matter of concern. This review presents the state‐of‐the‐art advances on the investigations of the adverse effects of NMs, including the potential exposure routes of nano‐TiO2 (e.g. respiratory system, skin absorption and digestive system), the physico‐chemical characterizations of nano‐TiO2 (e.g. crystal structure, shape,size, zeta potential, treatment media, aggregation and agglomeration tendency, surface characteristics and coatings), risk evaluation of nanotoxicity (e.g. cytotoxicity, ecotoxicity, phototoxicity, and phytotoxicity) and potential mechanisms of adverse effects (e.g. generation of reactive oxygen species, oxidative stress and organelle dysfunction). The review aims to facilitate scientific assessments of health risks to nano‐TiO2, which would guide the safe applications of NMs in our daily life. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
104.
T-cell lymphoblastic lymphoma (T-LBL) is a highly aggressive form of lymphoma with poor clinical outcomes and no standard treatment regimen. In this study, we assessed the safety and efficacy of tandem autologous hematopoietic stem cell transplantation (auto-HSCT) for adult T-LBL and evaluated prognostic factors affecting survival. A total of 181 newly-diagnosed adult T-LBL patients were enrolled: 89 patients were treated with chemotherapy alone, 46 were allocated to the single auto-HSCT group, 46 were treated with tandem auto-HSCT. Median follow-up time was 37 months; the 3-year progression/relapse rate of the tandem auto- HSCT group was significantly lower than that of the single auto-HSCT and chemotherapy groups (26.5% vs. 53.1% and 54.8%). The 3-year progression- free survival (PFS) and overall survival (OS) rates of the tandem auto- HSCT group (73.5% and 76.3%) were significantly higher than those of the single auto-HSCT group (46.9% and 58.3%) and the chemotherapy group (45.1% and 57.1%). In the tandem auto-HSCT group, age and disease status after the first transplant impacted OS and PFS. Multivariate analysis identified that disease status after the first transplant was the only independent prognostic factor for patients treated with tandem-HSCT. In addition, diagnostic models of the initial CD8+CD28+/CD8+CD28 T-cell ratio in predicting the disease status were found to be significant. Taken together, tandem auto- HSCT can be considered an optimal strategy for adult T-LBL patients. (Study registered at: ChiCTR-ONN-16008480).  相似文献   
105.
非技术性服务质量对于现代医院来讲意义重大。评价指标体系是对其进行评价而改进其质量为前提和关键。该研究从指标体系的构建、指标体系的确立以及指标体系的考核三个方面研究了江苏省医院非技术服务质量评价指标体系。  相似文献   
106.
围手术期的医疗质量一直是医院医疗质量与安全的重中之重。如何才能管理好围手术期医疗质量,一直是让人棘手的问题。南通大学附属医院借鉴三级医院等级评审中广泛使用的PDCA质量管理循环及系统追踪并将其灵活运用,在医院围手术期质量管理中起到良好的效果。  相似文献   
107.
目的:分析比较胰腺脓肿及胰腺坏死感染的临床特点、病原学特征、诊治措施和转归,以期改善其预后.方法:对1991年1月~2002年12月北京协和医院诊治的胰腺脓肿患者13例,胰腺坏死感染患者2例进行回顾性分析,比较其临床特点、诊断和治疗结果及预后.结果:(1)腴腺脓肿和胰腺坏死感染的好发因素有重症胰腺炎、手术后胰腺炎、囊肿穿刺引流.(2)所有患者病程中均有持续发热或体温降而复升,可伴或不伴腹痛、血白细胞和淀粉酶升高.(3)引流液细菌培养阳性率100%,由高到低依次为肠杆菌、绿脓杆菌、肠球菌、葡萄球菌和类酵母菌等,73.3%(11/15)为混合感染.(4)在内科支持治疗基础上全部患者行局部穿刺置管或手术清创引流,80%(12/15)好转出院,20%(3/15)死亡或放弃治疗.结论:(1)对持续中等度以上发热大于3周或体温下降后再次上升者,适时进行胰腺穿刺可以获得早期诊断.(2)积极的外科或介入治疗,同时密切监护、加强抗感染和全身支持治疗,有可能改善患者的预后.(3)与手术相比,介入治疗在胰腺脓肿中的应用前景有待进一步研究.  相似文献   
108.
BACKGROUND: Biomechanical properties in terms of residual strains in diabetic small intestine have not been studied. Furthermore, no data have been reported on affect of gliclazide on gastrointestinal complications of diabetes. AIMS: To determine remodelling of zero-stress state of small intestine in streptozotocin-induced diabetic rats and effect of gliclazide treatment. MATERIALS: Morphological properties and residual strains were studied in duodenum, jejunum and ileum obtained from diabetic rats, gliclazide-treated diabetic rats and normal rats (n = 8 each group). METHODS: Diabetes was induced by single intraperitoneal injection of 65 mg/kg streptozotocin. Gliclazide (10 mg kg(-1) day(-1) was injected directly into stomach lumen by intragastric gavage twice daily. Experimental period was 35 days. To approach no-load state; intestinal segments were surgically excised and cut transversely into short ring-shaped segments. Each ring was cut radially to obtain geometry of zero-stress state. Circumferential length, the wall thickness and opening angle were measured from digital images of each specimen and residual strains were computed. RESULTS: Blood glucose level of diabetic group (approximately 20 mmol/l) was consistently higher than that in normal group (approximately 4 mmol/l) after induction of diabetes (p < 0.001). Gliclazide lowered average blood glucose level to between 10 and 15 mmol/l (p < 0.001). Plasma insulin levels of both diabetic groups (average between 10 and 15 pmol/l) were significantly lower than those in normal group (average approximately 18 pmol/l, p < 0.05). Wet weight per unit length and wall thickness of duodenum, jejunum and ileum were significantly higher in Diabetes group than those in Normal group (p < 0.05). Opening angle and absolute value of residual strain were significantly smaller in duodenum and larger in jejunum and ileum in Diabetes group than in Normal group (p < 0.001). Gliclazide treatment partly restored these changes (p < 0.05). CONCLUSIONS: Diabetes induced morphometric and biomechanical remodelling in intestine. Gliclazide partly restored these changes.  相似文献   
109.
目的 分析深圳市2015—2020年放射工作人员上岗前职业健康检查染色体畸变率与微核率的水平及其分布特征,为加强放射工作人员辐射防护和职业健康管理提供科学依据。 方法 选取2015—2020年在深圳市职业病防治院接受上岗前职业健康检查的2 777名放射工作人员开展横断面研究,其中男性2 210名、女性567名,年龄17~69(27.6±6.8)岁,将受检者按年龄分为5组:17~20岁、21~30岁、31~40岁、41~50岁、51~69岁。采用全血微量培养法制备受检者的淋巴细胞微核和染色体,应用全自动染色体扫描分析系统对每名受检者的100个淋巴细胞染色体中期分裂相进行分析,统计双着丝粒体、着丝粒环和无着丝粒体等染色体畸变类型,比较不同年龄组以及同年龄组不同性别受检者染色体畸变情况和微核情况的差异。计量资料的组间比较采用方差分析;染色体畸变和微核的分布服从泊松分布,采用非参数检验,2组间比较采用Mann-Whitney U检验,多组间比较采用Kruskal-Wallis秩和检验。受检者年龄与染色体畸变率、微核率的相关性分析采用Spearman秩相关分析。 结果 2 777名受检者的染色体畸变(双着丝粒体+着丝粒环+无着丝粒体)率为(0.072±0.005)%、双着丝粒体+着丝粒环畸变率为(0.016±0.002)%、染色体畸变细胞率为(0.068±0.005)%、微核率为(0.43±0.01)‰、微核细胞率为(0.40±0.01)‰、淋巴细胞转化率为(85.07±3.16)%。各年龄组间染色体畸变率、双着丝粒体+着丝粒环畸变率、染色体畸变细胞率以及各年龄组不同性别受检者的染色体畸变率、染色体畸变细胞率间的差异均无统计学意义(χ2=1.193、0.931、0.691,Z=?0.929~?0.059,均P>0.05)。与17~20岁年龄组相比,其余各年龄组受检者的微核率、微核细胞率均较高,淋巴细胞转化率均较低,且差异均有统计学意义(Z=?6.981~?2.510,F=4.922~52.860,均P<0.05);受检者的微核率和微核细胞率均与年龄呈正相关(r=0.166、0.168,均P<0.001),而淋巴细胞转化率与年龄呈负相关(r=?0.197,P<0.001);21~30岁年龄组、31~40岁年龄组女性受检者的微核率、微核细胞率以及17~20岁年龄组、21~30岁年龄组女性受检者的淋巴细胞转化率均显著高于同年龄组的男性受检者,且差异均有统计学意义(Z=?4.826~?3.516,F=6.947、14.563,均P<0.01)。 结论 深圳市2015—2020年放射工作人员上岗前职业健康检查染色体畸变率与微核率均未超过国内文献报道的健康人群的本底水平范围,但有随年龄增大而升高的趋势,需加强放射工作人员的辐射防护与职业健康管理。  相似文献   
110.
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